## Oj-Algo - Matrix exponential - java

I resolve the following equation :
To solve it, I would like to use matrix exponential :
I thought about 3 ways to do it :
I could have missed it but Oj-Algo could have a simple way to compute exp(A) (I did not find it in MatrixStore javadoc)
I get matrix D and V from EigenValue methods ([A] = [V][D][V]-1) and then I compute
Then the question that comes first is how I apply x->exp(x*t) function to all diagonal elements of D ?
Last idea is basically the same as 2. but I previously store the scalar-matrix product in a new matrix ([X] = [D]*(-t)) and then I compute :
Can you help me find the best way/methods/class I should use ? Thank you
NB : This question is a "follow up question" : initial question

## Related

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### Where can i get a Java implementation of Dijkstra's algorithm? [closed]

I am looking for a generic Java implementation of Dijkstra's algorithm. I've tried coding this up on my own, but I keep running into problems. If it helps, I know for a fact that the graph is always connected. Does anyone know of such an implementation? Thanks!

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JGrapht is a common Java library for graphs. dijkstra's algorithm is implemented too.

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Good resources from Universities From New York University at http://www.cs.nyu.edu/~vs667/development/~DijkstraAlgorithm/ From Princton University at http://algs4.cs.princeton.edu/41undirected/Graph.java.html Also vogella made a nice implementation at http://www.vogella.com/articles/JavaAlgorithmsDijkstra/article.html